The turbine rotor is a key element in the aerospace engine and gas turbine. In a severe operation condition, such as high temperature and high rotating speed, a stable operation of the turbine rotor for a long time is required. Complicate loads, such as a centrifugal force generated by high rotating speed, a thermal stress, an aerodynamic force of the gas or vapor and vibration load, are exerted on the rotor disc and blades of the turbine rotor, which forms a stress state mainly composed of the tensile stress. Therefore, turbine materials must have a high strength and an excellent fatigue resistance at a high temperature.
However, if the blade or the rotor disc of the turbine rotor was broken into fragments, the fragments would be splashed with a high speed due to the large centrifugal force, and damage the engine and the other components seriously.
In order to improve the safety, the reliability and the working performance of the turbine rotor, variant superalloys having an excellent high-temperature performance, such as the nickel-based alloy, the cobalt-based alloy, the iron-based alloy or the titanium-aluminum alloy, have been developed. In addition, many materials and manufacturing technologies of the directional crystallization blade and the single crystal blade also have been developed. The technologies improve the operating performance of the turbine rotor by means of enhancing the high-temperature performance of the materials of the turbine rotor or reducing the operating temperature of the turbine rotor. However, the force and the stress state applied on the turbine rotor are not changed much, such that the working loading of the turbine rotor is not optimized at all.